Metabolism remains stable between ages 20 and 60

A study published in the journal ‘Science’ indicates that metabolic rates remain largely stable between the ages of 20 and 60 when accounting for body size and composition. Contrary to common belief, aging does not necessarily mean a slowing metabolism.

Weight gain with age is often attributed to changes in body composition and lifestyle. Starting in the mid-30s, adults may lose muscle mass at a rate of approximately 1% annually without strength training. Since muscle tissue consumes more energy at rest than fat, this loss reduces overall calorie burning.

Additionally, physical activity levels often decline over time. Research tracking 963 individuals aged 38 to 50 over a decade showed an average increase in sedentary time of 40 minutes per day and a decrease in light physical activity by 30 minutes. Other contributing factors include lifestyle changes, such as long working hours, late-night eating, and hormonal shifts in women during perimenopause and menopause, which can alter fat storage patterns.